Sydney FC will be furious at the loss as they actually were the better side but a controversial goal just nine minutes in to the match was enough for Perth to claim the victory.
The goal came from a penalty after Ryo Nagai was brought down by Vedran Janjetovic which was clear cut but Nagai was well offside when the cross came in meaning that the penalty should never have been called.
Sydney protested the decision while Ben Williams stood firm, booking Janjentovic for the foul and Nick Carle for dissent as his assistant never raised his flag for the offside infringement. That allowed Steven McGarry to step up and slam the penalty home to give Perth an early lead.
Perth were then left fuming about an offside call of their own as in the 23rd minute Maclaren was able to break free of the Sydney defense getting one-on-one with Janjentovic only to be called offside despite appearing to start from an onside position, perhaps evening out the incorrect decision on the goal.
It was a tense opening half with the challenges flying in and cards being shown and while Sydney were able to create chances Danny Vukovic was at his best to keep them out.
Sydney's best chance of the half was also the worst miss of the match as Ali Abbas was left open in the box but couldn't get his header on target letting Perth off the hook and sending Perth to the break 1-0 up.
The Sky Blues continued to go for an equalizer in the second half and in the 56th minute were inches from finding it as Richard Garcia got a header away but could only send it over the bar.
Perth responded and also went close as Ryan Edward played McGarry through as he outpaced Tiago Calvano and shot just wide of goal.
Matt Thompson was able to provide a solid chance for Sydney in the second half as he shot powerfully low for goal but Vukovic got down well to send the ball out for a corner.
Sydney's chances of finding a win significantly improved in the 63rd minute when their star player, Alessandro Del Piero made his return off the bench and showed his class by turning down the captain's arm band from Brett Emerton.
That was about the biggest impact Del Piero had on the match as he still struggled to shake off his calf injury while Perth Glory's own returning substitute, Shane Smeltz also failed to have the desired impact.
Smeltz did create chances late on in the match making plenty of runs but just wasn't able to get an assist or find a goal but it showed good signs for Glory and New Zealand going forward as Perth managed a 1-0 win.